Table of contents
3820 GROUP USER’S MANUAL
iv
2.10 Reset ..................................................................................................................................2-185
2.10.1 Explanation of operations..........................................................................................2-185
2.10.2 Internal state of the microcomputer immediately after reset release.........................2-187
2.10.3 Reset circuit...............................................................................................................2-188
2.10.4 Notes on the RESET pin ...........................................................................................2-189
2.11 Oscillation circuit.............................................................................................................2-190
2.11.1 Oscillation circuit........................................................................................................2-190
2.11.2 Internal clock
φ
..........................................................................................................2-192
2.11.3 Oscillating operation..................................................................................................2-194
2.11.4 Oscillation stabilizing time .........................................................................................2-197
CHAPTER 3. APPENDIX
3.1 Built-in PROM version..........................................................................................................3-2
3.1.1 Product expansion...........................................................................................................3-3
3.1.2 Performance overview.....................................................................................................3-4
3.1.3 Pin configuration..............................................................................................................3-5
3.1.4 Functional block diagram ................................................................................................3-8
3.1.5 Notes on use ...................................................................................................................3-9
3.2 Countermeasures against noise .......................................................................................3-11
3.2.1 Shortest wiring length....................................................................................................3-11
3.2.2 Connection of a bypass capacitor across the V
SS
line and the V
CC
line.......................3-12
3.2.3 Oscillator concerns........................................................................................................3-13
3.2.4
Installing an oscillator away from signal lines where potential levels change frequently............................
3-14
3.2.5 Oscillator protection using V
SS
pattern..........................................................................3-14
3.2.6 Set up for I/O ports ........................................................................................................3-14
3.2.7 Providing of watchdog timer function by software .........................................................3-15
3.3 Control registers..................................................................................................................3-16
3.4 List of instruction codes ...................................................................................................3-29
3.5 Machine instructions...........................................................................................................3-30
3.6 Mask ROM ordering method.............................................................................................3-40
3.7 Mark specification form .....................................................................................................3-52
3.8 Package outlines .................................................................................................................3-54
3.9 SFR allocation......................................................................................................................3-56
3.10 Pin configuration ...............................................................................................................3-57